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burnt-resistor
1D Chess rowan441.github.io

hackyhacky40 minutes ago

If you enjoyed this, you might like Mind Chess, which can be played without a board and pieces [1]:

Consider Mind Chess. Two players face each other. One says "Check." The other says "Check." The first says "Check." This continues until one of them says, instead, "Checkmate." That player wins -- superficially. In fact, the challenge is to put off checkmate for as long as possible, while still winning. This may be better stated: you truly win Mind Chess if you call "Checkmate" just before your opponent was about to.

[1] http://www.eblong.com/zarf/essays/mindgame.html

quuxplusone2 hours ago

Mentioned in TFA: This version of chess is given by Martin Gardner in his "Mathematical Games" column of July 1980 (pages 27 and 31) — https://www.jstor.org/stable/24966361 — and the analysis of White's mate is given in the column of August 1980 (page 18) — https://www.jstor.org/stable/24966383.

I do wonder how things would change if the board were 9 cells long; 10 cells long; etc. Also, it seems "in the spirit" to permit castling if neither K nor R has moved yet: i.e., from the position

K _ R N r _ n k

White ought to be permitted to

_ R K N r _ n k

(Or maybe there's a stronger argument for R K _ N r _ n k, actually. The former was conceptually "rook moves halfway toward king, then king moves to the other side of rook"; but the latter is "rook moves two steps in king's direction while king moves to the other side of rook.")

I'm pretty sure this wouldn't change the analysis on the 8-cell board at all, though. I wonder if it would change the analysis on any size of board.

al_borlandan hour ago

Maybe I'm not good enough at chess to understand the strategy here, but how would castling be useful in this 1-D game? Castling in a normal game protects your King and activates the Rook. In this 1-D game, your King starts out protected behind the Rook. If you castle and end up in a _ R K N position, your king is exposed and your Rook is trapped behind the King, useless, with no way to ever get it back out. The Rook seems essential for mate, and its power has been eliminated.

teiferer13 minutes ago

Exactly. Feels like R K N would be a more suitable initial position in which castling would swap the king into safety, provided it has not moved and is not in check...

Though maybe in that case the best first move for both is to castle and we are non the wiser (back to the original starting position)

juleiiean hour ago

That finally confirmed that I am too regarded for chess if even 1D is too hard yay

amrrsan hour ago

is that str.replace(g,t) ?

juleiie14 minutes ago

No. I am actually too highly regarded for measly single dimensional game

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aktenlage16 minutes ago

Very cool. Reminds me of 1D Pacman: https://abagames.itch.io/paku-paku

asibahi2 hours ago

This is really nice.

Incidentally, there is an actual 1D game that is one of the most popular games on the planet: Backgammon.

zniturahan hour ago

Good observation. Considering stacking of pieces maybe 1.5D though.

a3w40 minutes ago

Chess has different pieces, which has higher entropy than a true 1d backgammon or 1d checkers with only one piece a field.

You could play with pieces that have a value of 1..N instead. Starting with 2,3, and 5 value pieces, and splitting them as needed. Making it one-dimensional again, while keeping 100% of the rules.

Final verdict, therefore: backgammon is 1D, not 1.5.

We could pretend that the second dimension was not playing a role in tactics back then, since it was very recently invented, like the brothers Wright invented the third dimension a hundred years ago. Or some hot air balloon at a world faire did it.

etskinner39 minutes ago

Mancala is roughly 1D too!

moffkalastan hour ago

Backgammon, the game everyone's seen and at the same time nobody knows how to play :P

Sharlin33 minutes ago

I learned to play backgammon because it was one of the three games on my Nokia phone circa 2001 :P

gef2 hours ago

Reminds me of Edwin A. Abbott's Flatland, where he describes Lineland. A one-dimensional world whose King can only move forward and backward, cannot conceive of sideways, and considers his tiny segment of existence complete and sufficient. The Linelanders are portrayed as pitiable, intellectually imprisoned by their single dimension. Much like us in our three :)

hypendev27 minutes ago

Don't know when was the last time I had so much fun with chess. Quite intuitive, clicked on the first click.

Would enjoy so much if there were more of these, feels like an obligation-free chess puzzle.

northfield272 hours ago

Haha, i was taking N4 and N6, but didn’t figure the steps after that.

To win we need to let knight die because rook can move multiple steps to kill the king.

From a third person perspective R2 is a deceptive move that takes advantage algorithm to make the black king back off to kill its knight.

aNapierkowskian hour ago

you could also just move your king on that move same result knight cant move, only king can, so it has to back away

palata2 hours ago

It was a lot more fun than I first thought!

sieste2 hours ago

It took me an embarrassing number of attempts to win.

hart_russell44 minutes ago

I don’t know why this is stalemate: N4 N5, N6 K7, R5. Wouldn’t rook have the king in checkmate?

Scarblac42 minutes ago

The rook doesnt attack the king because N6 is in the way.

So black is not in check and has no legal moves, so stalemate.

_air42 minutes ago

Black has no legal moves because of the knight but they aren't in check

darepublican hour ago

I won after four attempts. Pretty sure it was perfect play so yes white has forced win

sdthjbvuiiijbb25 minutes ago

Yeah. I think 1. N4 leads to a white win. It's fairly easy to verify that a black rook move will lead to a white win (1...R5 2. R2 and 1...Rx4 2. Rx4 N5 3. Rx5#). So the critical line is 1. N4 N5, but then 2. Nx6+ K7 3. R4 also leads to a win: 3...Kx6 4. K2 K7 5. Rx5# and 3...N3+ 4. K2 N5 5. N8 Kx8 6. Rx5#.

There are probably other ways to win too.

kkaske2 hours ago

I was only able to beat this after a couple retries. The hint was hard to read.

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tempestnan hour ago

That's actually a fun little puzzle.

schmeichel2 hours ago

Finally, a version of Chess I can understand. Thank you.

bbx2 hours ago

Oh very interesting. Even with these restrictions, there are quite a few variations, and it seems only one ends up with white winning.

addybojanglesan hour ago

Silly nice brain teaser

sjdv198239 minutes ago

Zugzwang!

rOOmbambar92 hours ago

It's very interesting and fun!)

lschueller2 hours ago

Cool idea. This is smart and lean. I like it

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tkapin2 hours ago

Nice! :)

vladde2 hours ago

i could not beat it, and i can't read that chess notation

thesuitonym2 hours ago

The letter is the piece to move, and the number is the index to move to, starting from 1 on the left. The first alphanumeric pair is your move, then the computer's move. Comma. Your move, computer's move...

qup2 hours ago

The first move after the comma is yours (open with kNight to 4), and the second move is apparently predetermined or always chosen.

DrammBA2 hours ago

the notation is just an array of move tuples, each tuple contains 1 move for white and 1 move for black, where each move is written as <1st letter of piece name><destination square>

burnt-resistorop42 minutes ago

There's a coordinate-based solution in the source code issues. I couldn't elucidate that notation either.

https://github.com/Rowan441/1d-chess/issues/1

Edit: There's a second solution where instead of moving the rook back 2, move the king forward one and the take the black knight with the rook as the checkmate move.

naorz3 hours ago

Fun stuff, love it!

BiraIgnacioan hour ago

love it!

tintor2 hours ago

The first move is always: white rook takes black rook, then the only remaining move for black is to move the knight away, which results in checkmate.

nippoo2 hours ago

If you play the game, you realise this ends up in stalemate.

Fabricio20an hour ago

I'm not very good at chess, but I dont get why most things are considered a stalemate? I strategically remove all pieces of the enemy, leaving only the king against my rook/tower whatever its called, the king has nowhere to run. In my eyes it's a checkmate. The game just calls it a stalemate. Would be a stalemate if I couldn't do anything, but I can kill the enemy king.

rokkamokkaan hour ago

There is an explanation further down. A stalemate is if the enemy has no valid loves and is not in check

al_borlandan hour ago

It's a stalemate because while the king can't move, he isn't under active attack. There is nowhere he can legally move, but he's safe where he's at.

jandrese2 minutes ago

That rule caught me up too. In regular chess if it is your opponents turn and their only piece is a king in the 1,8 square, and you have rooks in the 2,1 and 8,7 squares that counts as a victory does it not?

umanwizardan hour ago

Black can’t move the knight: it’s illegal to make a move that puts yourself in check. Thus black has no legal moves, but isn’t in check, so the result is a draw.

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